Environment
Alireza Yousefi Kebriya; Mehdi Nadi; Ebadat Ghanbari Parmehr
Articles in Press, Accepted Manuscript, Available Online from 28 December 2023
Abstract
Mazandaran province, due to its strategic geographical location and high influx of tourists during holidays, coupled with the presence of power plants and industrial complexes, is facing pollution challenges. This research, conducted in 2022, focuses on monitoring nitrogen dioxide and ozone pollutants ...
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Mazandaran province, due to its strategic geographical location and high influx of tourists during holidays, coupled with the presence of power plants and industrial complexes, is facing pollution challenges. This research, conducted in 2022, focuses on monitoring nitrogen dioxide and ozone pollutants in the province and investigating the role of tourists during certain multi-day holidays. Utilizing Sentinel 5 satellite imagery, including daily images from holidays and non-holidays, the study compensates for the lack of regular pollution data in Mazandaran's monitoring stations by validating the satellite data against Tehran stations. Linear regression equations determine the levels of nitrogen dioxide and ozone pollutants, leading to the creation of an Air Quality Index map for Mazandaran during holidays. The results highlight a strong correlation (0.3-0.7) between satellite and ground data, with ozone pollutants exhibiting a higher correlation. The skew error is consistently zero, and the mean square error varies between 1.9-6.2 PPb for nitrogen dioxide and 1.1-5.1 PPb for ozone. Pollution estimates for different points in Mazandaran during holidays and non-holidays indicate higher ozone pollution compared to nitrogen dioxide. Ozone pollution is particularly unhealthy and very unhealthy during holiday periods, especially along the coastal areas, while non-holiday days show cleaner and healthier air quality. The pollution index map illustrates higher ozone pollution in coastal cities during holidays compared to other regions, emphasizing the impact of tourists. This research demonstrates the effectiveness of Sentinel 5 satellite in monitoring air pollution and underscores the significant influence of tourists and transportation on Mazandaran province's air quality.
Environment
Elaheh faghihnasiri; Farhad Qaderi; S. Mustapha Rahmaninezhad
Articles in Press, Accepted Manuscript, Available Online from 30 January 2024
Abstract
Industrial processes are among human activities that cause the production of a large volume of wastewater containing organic pollutants such as phenol and its derivatives. Soil remediation is crucial for enhancing environmental quality for both humans and other living organisms. This study investigated ...
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Industrial processes are among human activities that cause the production of a large volume of wastewater containing organic pollutants such as phenol and its derivatives. Soil remediation is crucial for enhancing environmental quality for both humans and other living organisms. This study investigated the use of an electro-peroxone system to remove environmental pollutants from soil. In conjunction with ozonation, the study employed electrochemically generated hydrogen peroxide using a carbon electrode, addressing concerns about transportation and storage. Experiments were structured using response surface methodology (RSM) with three variables: ozone dosages ranging from 4 to 8 l/hr, initial pollutant concentrations from 20 to 50 mg/kg, and treatment durations between 7 and 14 days. The effectiveness of phenol removal from soil was assessed by applying a consistent voltage of 2 V/cm to the soil samples in all experiments. Results revealed a negative correlation between initial pollutant concentration and ozone consumption and a positive correlation between treatment duration and pollutant removal efficiency. Optimal removal efficiency occurred with a 14-day treatment duration, an 8 l/hr ozone dosage, and a 20 mg/kg initial pollutant concentration. The electro-peroxone system's application indicates its potential as a sustainable, eco-friendly, and cost-effective approach to soil remediation for pollution.
Environment
hassan Farsi; Mehrdad Rohani; Sajad Mohamadzadeh
Articles in Press, Accepted Manuscript, Available Online from 08 April 2024
Abstract
Facial feature recognition (FFR) has witnessed a remarkable surge in recent years, driven by its extensive applications in identity recognition, security, and intelligent imaging. The UTKFace dataset plays a pivotal role in advancing FFR by providing a rich dataset of facial images with accurate age, ...
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Facial feature recognition (FFR) has witnessed a remarkable surge in recent years, driven by its extensive applications in identity recognition, security, and intelligent imaging. The UTKFace dataset plays a pivotal role in advancing FFR by providing a rich dataset of facial images with accurate age, gender, and race labels. This paper proposes a novel multi-task learning (MTL) model that leverages the powerful Efficient-Net architecture and incorporates attention-based learning with two key innovations. First, we introduce an age-specific loss function that minimizes the impact of errors in less critical cases while focusing the learning process on accurate age estimation within sensitive age ranges. This innovation is trained using the UTKFace dataset and is specifically optimized to improve accuracy in age estimation across different age groups. Second, we present an enhanced attention mechanism that guides the model to prioritize features that contribute to more robust FFR. This mechanism is trained on the diverse and challenging images of UTKFace and is capable of identifying subtle and discriminative features in faces for more accurate gender, race, and age recognition. Furthermore, our proposed method achieves a 30% reduction in model parameters compared to the baseline network while maintaining accuracy. Extensive comparisons with existing state-of-the-art methods demonstrate the efficiency and effectiveness of our proposed approach. Using the UTKFace dataset as the evaluation benchmark, our model achieves a 0.62% improvement in gender recognition accuracy, a 2.35% improvement in race recognition accuracy, and a noteworthy 3.23-year reduction in mean absolute error for age estimation.
Environment
O. O. Obiukwu; M. N. Nwigwe; T. O. Uchechukwu; J. Azubuike; D. A. Ekpechi
Abstract
The experimental study of the physicochemical properties of biodegradable composite of sugarcane bagasse-polyester have been investigated. Natural composite materials having biodegradable property which makes them a material with limited lifespan, thereby there is a need to research on these materials ...
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The experimental study of the physicochemical properties of biodegradable composite of sugarcane bagasse-polyester have been investigated. Natural composite materials having biodegradable property which makes them a material with limited lifespan, thereby there is a need to research on these materials beyond their normal scope before their lifespan for solid material applications as current technological concepts advances. In this research, water absorption, specific gravity, and chemical resistance test were conducted on sugarcane bagasse polyester composite of different specimen, using a laboratory beaker filled with distilled water, HCl, NaOH, H2O2, NaOCl and detergent solution, at a particular time observing a suitable ASTM. From the result obtained, specimen with 25 weights % increase in Sugarcane bagasse fibre loading, indicated water absorption value of 1.42 %, which could be acceptable for good resistance to water material. The chemical resistance test, severity of the attack and effect on the appearance and weight of the composites followed the order: 10% HCl > 10% NaOH solutions, the deteriorating effect of the composites showed to be unaffected by neither the amount of filler weight nor the presence of any additive incorporated in the SCB-PES composites.
Environment
A. C. Johnson
Abstract
The COVID-19 pandemic, which began during early 2020, had been a worldwide problem, resulting in significant fatalities. In China, the pandemic resulted in strict lockdowns, restricted movement, and reduced transportation. This resulted in improvement of air quality in many cities in China. The objective ...
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The COVID-19 pandemic, which began during early 2020, had been a worldwide problem, resulting in significant fatalities. In China, the pandemic resulted in strict lockdowns, restricted movement, and reduced transportation. This resulted in improvement of air quality in many cities in China. The objective of the study is to compare the nature of air quality pre-COVID period (2018-2019) and during COVID period (2020-2201). The following air quality parameters were investigated, air quality index (AQI), particulate matter (PM2.5 and PM10), sulphur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3), and carbon monoxide (CO). The present investigation results will augment to the current understanding on the air pollution situation during the COVID-19 pandemic in Jiangsu Province in China. The study revealed that air quality in Jiangsu Province improved during the months when COVID-19 positive cases increased. The reduction in air pollutants concentrations started during 2020 and reached a maximum during 2021. Overall the air quality index (AQI) improved by 8.2 % and air pollutant reductions achieved were, PMs (≈ 21%), SO2 (26.2 %), NO2 (13.6 %), O3 (2.4 %) and CO (10.4 %). Cities in Jiangsu Province with high air pollutant concentrations achieved a moderate reduction. The correlation between air pollutants and AQI was positive except for O3. The implications of the study are, reduction of fossil fuel powered vehicles and industrial activity can make notable positive impact on the air quality of the region.
Environment
O. F. Anjorin; L. C. Imoh; C. Uhunmwangho
Abstract
Since actual metal emissions can be assessed using Particulate matter (PM) as a proxy, monitoring and controlling metal compounds in biomass emissions is essential for determining their quantities and potential health effects. Using a low volume respirable dust sampler, indoor ambient metal-bearing particles ...
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Since actual metal emissions can be assessed using Particulate matter (PM) as a proxy, monitoring and controlling metal compounds in biomass emissions is essential for determining their quantities and potential health effects. Using a low volume respirable dust sampler, indoor ambient metal-bearing particles were quantified in-situ and collected from nine (9) randomly selected public kitchens of boarding secondary schools in Jos, Plateau State. Atomic absorption spectrometry (AAS) was used to determine the amounts of specific heavy metals in these collected samples. Additionally, 114 responders' blood samples underwent a biochemical lead assay study. The mean concentrations of the samples taken for Mn, Cd, Cu, Fe, Cr, Zn, Ni, Pb, and Co were 0.097, 0.015, 0.254, 0.314, 1.027, 0.000, 0.076, 0.106, and 0.169 µg/m3, respectively. The results of the blood lead assay analysis showed that 54% of the subjects had B-Pb levels above 80 µg/dL, 33% had B-Pb levels between 40 µg/dL and 80 µg/dL, 8% between 25 µg/dL and 40 µg/dL, 4% between 10 µg/dL and 25 µg/dL, 4% below 10 µg/dL, and 15% below 10 µg/dL. In general, elevated levels of metal-bearing particles in the indoor environment public kitchens expose kitchen staff to several occupational hazards.
Environment
O. O. Obiukwu; M. N. Nwigwe; T. O. Uchechukwu; J. Azubuike; D. A. Ekpechi
Abstract
Various fiber-matrix combinations were used to create biodegradable composites using sugar cane bagasse (SCB) fiber and a polyester resin (PES) matrix. SEM, FTIR, mechanical testing, thermogravimetric analysis (TGA), and the method of soil burial were employed to assess the effects of the fiber content ...
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Various fiber-matrix combinations were used to create biodegradable composites using sugar cane bagasse (SCB) fiber and a polyester resin (PES) matrix. SEM, FTIR, mechanical testing, thermogravimetric analysis (TGA), and the method of soil burial were employed to assess the effects of the fiber content (9-54 wt%), PLA (1-5.5 wt%), starch (1-5.5 wt%), and fiber treatment on the morphology of the surface, flexural, thermal, tensile as well as biodegradable qualities of polyester/sugar cane bagasse fiber biocomposites. The outcomes demonstrated that the optimal tensile strength of biocomposites, impact, and Flexural capabilities were attained by the 37 wt% treated sugar cane bagasse fibers. Tensile, flexural, and impact strength measurements for the 9, 18, 27, 37, 45, and 54 wt% biocomposites, respectively, ranged from 10.21 to 18.00, 21.33 to 28.12, and 12.21 to 15.67 Mpa. The results show that sugarcane bagasse-polyester composites demonstrated acceptable mechanical and multifunctional properties. This portrays the effectiveness of Sugarcane bagasse as reinforcement for Polyester matrix and its potential for eco-friendly fabrication of components.
Environment
A. Yousefi Kebriya; M. Nadi
Abstract
The Air Quality Index is a numerical tool used to quantify air pollution levels and classify pollution severity. It plays a vital role in ensuring healthcare system stability by understanding air pollution's dynamic behavior and shifts in pollution intensity. To analyze the probabilistic transition between ...
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The Air Quality Index is a numerical tool used to quantify air pollution levels and classify pollution severity. It plays a vital role in ensuring healthcare system stability by understanding air pollution's dynamic behavior and shifts in pollution intensity. To analyze the probabilistic transition between pollution severity levels, a Markov Chain model was utilized. This study examined six air pollution states (Clean, Healthy, Unhealthy for Sensitive Groups, Unhealthy, Very Unhealthy, Hazardous) across 12 stations in Tehran's northern, southern, eastern, western, and central regions from 2018 to 2022. Results revealed that the western and southern areas exhibited the highest pollution levels, with over 44% and 34% of instances corresponding to unhealthy indices, respectively. In contrast, northern Tehran consistently maintained cleaner air quality. Probability transition matrices highlighted the greatest stability continuity in healthy air quality across all regions. Transitioning between clean/healthy air to very unhealthy/hazardous air was minimal, with hazardous air quality almost absent in most stations, except for the west and south (25% stability). The probability of continued unhealthy air quality in these areas reached 60%, indicating heightened pollution. The findings of transition probability matrices indicated that the western and southern regions had the highest likelihood of sustained pollution, while the northern region consistently maintained cleaner air. The probability of continuous clean air in the west was below 30%, while transitioning from very unhealthy/hazardous air to unhealthy air reached 50%. Conversely, the northern Tehran region exhibited over 40% stability for unhealthy air quality and over 50% for clean and healthy air.
Environment
M. Bisong Obi; A. Abubakar; S. Yunusa; F. Mohammed
Abstract
This work investigated the optimization of process parameters for catalytic pyrolysis of waste tyre using reactivated spent Fluid catalytic cracking (FCC) catalyst. The waste tyre pyrolysis used design expert software as the optimization tool for this study. A 3-factor level CCD with 20 experimental ...
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This work investigated the optimization of process parameters for catalytic pyrolysis of waste tyre using reactivated spent Fluid catalytic cracking (FCC) catalyst. The waste tyre pyrolysis used design expert software as the optimization tool for this study. A 3-factor level CCD with 20 experimental runs was used with temperature, time and catalyst as the input parameters while oil yield, density and viscosity were the output variables. Thereafter, an experimental validation of the optimized parameters, which were not among the original experimental runs, was carried out. Pyrolysis was also carried out at the optimized conditions with un-reactivated catalyst and without catalyst to ascertain the contributions of the catalyst and its reactivation. Based on the optimum parameters, 48.5 wt. % oil (0.79 g/ml and 2.05 cSt) was produced with the reactivated catalyst, 43.4 wt. % (0.86 g/ml and 3.52 cSt) was produced with spent catalyst, and 51 wt. % oil (0.95 g/ml and 4.24 cSt) was produced without catalyst. The oil yield without catalyst was higher than with reactivated catalyst (R-CAT); but it however had the lowest fuel qualities while oil produced with catalyst in turn had higher quantity and quality compared to oil produced with catalyst. Therefore, the incorporation of density and viscosity of the oil in the optimization of the catalytic pyrolysis of waste tyre enhanced the improvement of yield and quality of the oil produced.
Environment
A. Shola Rinde; A. Mustapha; A. Francis Olatunbosun
Abstract
Harmattan dust has been identified as a discrete mass of solid earth crust hanging in the air for an extended period of time. It has been noted that less studies have been conducted in Nigeria to determine the functional groups contained in harmattan dust. The goal of this study was to figure out what ...
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Harmattan dust has been identified as a discrete mass of solid earth crust hanging in the air for an extended period of time. It has been noted that less studies have been conducted in Nigeria to determine the functional groups contained in harmattan dust. The goal of this study was to figure out what functional groups and chemicals that were present in the dust. Usmanu Danfodiyo University, Sokoto (12°N, 13.8°E), Kebbi State University of Science and Technology, Aliero (12.3070°N, 4.4955°E), Federal University of Agriculture, Zuru (11.4058°N, 5.2400°E), and Waziri Umaru Federal Polytechnic, Birnin Kebbi (12.4601°N, 4.4955°E), were the selected stations used in this study. The suspended Harmattan dust samples were obtained in glass petri plates using a direct deposition approach. Fourier Transform Infrared Spectroscopy (FTIR) and Gas Chromatograph-Mass Spectrometry (GC-MS) were used to examine the samples collected. The results show that eleven functional groups were present in the samples, including =CH-H, -CH3, N-H, C=C, =C-H, C-H, O-H, C-N, C=O, C-O-C, and -CH3. According to GC-MS, the component (2-methoxy ethyl) had the greatest quality value (Q-Value) of 83, area percentage corresponding to time rating (RT) of 13.647, and CAS 018173-63-2 in the dust samples. It is therefore recommended that the Federal Republic of Nigeria's government increase funding for the research centers so that researchers can study all cities in the country and better observe the functional group metals present in the harmattan dust.
Environment
M. J. Islam
Abstract
Dhaka, the capital of Bangladesh, is encircled by six rivers like a garland. Dhaka's growing population, urbanization, and modernization are causing problems with wastewater discharges and water pollution in the river's water body. These rivers receive wastewater from numerous sources, which are discharged ...
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Dhaka, the capital of Bangladesh, is encircled by six rivers like a garland. Dhaka's growing population, urbanization, and modernization are causing problems with wastewater discharges and water pollution in the river's water body. These rivers receive wastewater from numerous sources, which are discharged as industrial effluents, municipal sewage, household wastes, clinical wastes, and oils. The water of these rivers is being polluted to an increasing degree. This study investigated how the surface water in Dhaka's rivers varies throughout the year. The results of various water quality indices, such as DO, BOD, COD, pH, TDS, EC, SS, Turbidity, and alkalinity, were compared with the guidelines set by Bangladesh's Department of Environment (DoE) and the World Health Organization (WHO). Sample collection was done in two seasons in a year, dry season and wet season. In this study, researchers also aim to determine the effect of this wastewater on the river water and thus provide a report on the state of a numerical rating for determining the rivers' water quality.
Environment
A. Sezavar; H. Farsi; S. Mohamadzadeh
Abstract
Person re-identification (re-id) is one of the most critical and challenging topics in image processing and artificial intelligence. In general, person re-identification means that a person seen in the field of view of one camera can be found and tracked by other non-overlapped cameras. Low-resolution ...
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Person re-identification (re-id) is one of the most critical and challenging topics in image processing and artificial intelligence. In general, person re-identification means that a person seen in the field of view of one camera can be found and tracked by other non-overlapped cameras. Low-resolution frames, high occlusion in crowded scene, and few samples for training supervised models make re-id challenging. This paper proposes a new model for person re-identification to overcome the noisy frames and extract robust features from each frame. To this end, a noise-aware system is implemented by training an auto-encoder on artificially damaged frames to overcome noise and occlusion. A model for person re-identification is implemented based on deep convolutional neural networks. Experimental results on two actual databases, CUHK01 and CUHK03, demonstrate that the proposed method performs better than state-of-the-art methods.
Environment
M. Heydari; T. Tabatabaie; F. Amiri; S. E. Hashemi
Abstract
Large volumes of contaminated industrial wastewater have caused growing concern among researchers and environmentalists. Benzene, toluene, ethylbenzene, xylene, and styrene (BTEXS) cyclic hydrocarbons in industrial effluents are often completely stable to biodegradation and must be treated before disposal. ...
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Large volumes of contaminated industrial wastewater have caused growing concern among researchers and environmentalists. Benzene, toluene, ethylbenzene, xylene, and styrene (BTEXS) cyclic hydrocarbons in industrial effluents are often completely stable to biodegradation and must be treated before disposal. In this context, using adsorption processes is a potential alternative for treating a wide range of organic pollutants, especially aromatic compounds in industrial wastewater. This study investigated the preparation of MCM-41 from silica; extracted from rice husk ash; MCM-41 was green synthesized to evaluate the effect of mesoporous used in BTEXS removal of an aqueous medium using the Taguchi method. The aqueous solution contains cyclic hydrocarbons was synthetically prepred based on real industrial effluent in concentrations of 50, 100, and 150 mg/l using MCM-41 catalysts, in doses of 0.1, 0.5, and 1g, at different pH values. In the present study, the optimum results obtained by Taguchi method analysis were pH =11, for duration of 60 minutes, the concentration of cyclic hydrocarbon solution BTEXS 100 mg/l, and nanoparticle dose of 0.5 g. The maximum BTEXS removal of 77.36% was achieved by the use of hydrogen peroxide.
Environment
J. E. Sani; T. S. Ijimdiya; G. Moses; A. A. Lawal
Abstract
The soil investigated for suitability checks, as a subgrade material in this study, was a crude oil contaminated (COC) soil treated using an electrokinetic technique. The index properties and compaction characteristics of the electrokinetic remediated (EKR) soil are natural moisture content was 10.97%; ...
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The soil investigated for suitability checks, as a subgrade material in this study, was a crude oil contaminated (COC) soil treated using an electrokinetic technique. The index properties and compaction characteristics of the electrokinetic remediated (EKR) soil are natural moisture content was 10.97%; The Atterberg limit test showed liquid limit, plastic limit, plasticity index and linear shrinkage of 36.50%, 22.05%,14.45 %, and 4.30%, respectively. The percentage of 62.80% passes 0.075mm sieve with a maximum dry density (MDD) of 1.77 Mg/m3, and the moisture content decreased from 13.2% to 11.81%. The soil is classified as A-6 according to AASHTO classification system and belong to clay of low plasticity CL or OL group according to the Unified Soil Classification System. The unconfined compression strength, (UCS), durability, and California bearing ratio (CBR) of the electrokinetic remediated soil improved marginally from 46.63kN/m2 to 92.64kN/m2; from 18% to 23%; and from 2.55% to 4.05% respectively. However, these results obtained, do not meet the minimum requirement of the Nigerian General Specification. As a result, it is advised for further research, that an EKR soil be stabilized using cement stabilization to achieve the desired subgrade strength.
Environment
A. Kaviani Rad
Abstract
A global health and economic crisis was caused by a pandemic Covid-19 in 2020, which reduced human activity worldwide. As human activities decreased, researchers had the chance to evaluate the impact of humankind on the ecosystem as well as explore the causes behind natural occurrences like forest fires, ...
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A global health and economic crisis was caused by a pandemic Covid-19 in 2020, which reduced human activity worldwide. As human activities decreased, researchers had the chance to evaluate the impact of humankind on the ecosystem as well as explore the causes behind natural occurrences like forest fires, which are mostly caused by humans. To assess the effect of quarantine on the forest fire situation in northern Iran. Twelve indicators were retrieved from Sentinel satellites, which represent four groups: land surface temperature, air pollutants, vegetation, and humidity. As indicated by preliminary results, the risk of fire decreased by about 34% in 2020 compared with 2018–2019; however, it subsequently increased again in 2021–2022. This leads to the conclusion that Covid-19 had a positive impact on forest health, but there was still an element of uncertainty as different ecological variables come into play. To evaluate this hypothesis in different regions, it is necessary to conduct additional studies, especially using ground-based data. In light of the adverse economic consequences of Covid-19, it is recommended that forest protection policies be implemented more effectively.
Environment
I. U. Siloko; E. A. Siloko
Abstract
This paper focuses on the interdependence between rainfall and temperature and their joint effect. Rainfall and temperature are vital climatic variables for agricultural productivity and other human activities. Despite the importance of rainfall and temperature, there are difficulties associated with ...
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This paper focuses on the interdependence between rainfall and temperature and their joint effect. Rainfall and temperature are vital climatic variables for agricultural productivity and other human activities. Despite the importance of rainfall and temperature, there are difficulties associated with accurate analysis of their joint distribution due to the possibility of interrelationship between the variables. Several studies have been conducted by researchers on the interaction between climatic variables in order to ascertain their effects on the environment because temperatures are observed to be undergoing changes regularly. The analysis of rainfall and temperature for exploratory and visualization purposes is investigated because underlying structures and patterns do form the basis of decisions by government and regulatory agencies. This study employs the statistical approach in investigating the interdependence between rainfall and temperature in Ekpoma, Edo State, Nigeria for a period of five consecutive years from 2016 to 2020 using the Gaussian kernel estimator. The results of the investigations using some statistical indicators establish that there is irregular pattern of rainfall which is occasioned by changes in temperature. The variability of rainfall is mostly prominent in two years which are 2017 and 2019 with 29.43mm and 27.74mm as maximum amount of rainfall respectively. The results also demonstrate that the performance of years with high standard deviations are better than that of low standard deviations. Again, the performance of years with high negative correlation coefficients and high negative covariance of rainfall and temperature is better than years with weak correlations and low covariance.
Environment
U. N. Wilson; J. E. Sani; A. Yusuf; O. C. Eze
Abstract
This research work examined the effect of jute fibre on the shear strength of concrete. Fibre volume fractions of 0%, 0.25%, 0.5%, and 0.75% for grades 25, 30, 35 and 40 N/mm2 respectively were used. A total of 32 beams and 96 cubes were prepared. 16 beams and 48 cubes were cured at room temperature ...
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This research work examined the effect of jute fibre on the shear strength of concrete. Fibre volume fractions of 0%, 0.25%, 0.5%, and 0.75% for grades 25, 30, 35 and 40 N/mm2 respectively were used. A total of 32 beams and 96 cubes were prepared. 16 beams and 48 cubes were cured at room temperature for 28 days, while the other 16 beams and 48 cubes were cured for 28 days and kept for a period of 6 months to be observed for durability with respect to strength after testing. All the beams were tested under three-point loading system with a shear span, av = 2.5d. The results of the compressive strength showed that concrete made with 0.5% jute fibre for 28 days and 6 months gave percentage increase in compressive strength by 12%, 12.5%, 9.7% and 10.1% for grades 25, 30, 35 and 40 N/mm2 respectively compared to the control samples. Percentage increase in shear strength were by 24.5%, 16.1%, 27.9% and 16.5% for concrete grades 25, 30, 35 and 40 N/mm2 respectively compared to the control samples. The addition of the fibre to the concrete slightly reduced the workability of the concrete and increased the crack resistance of concrete.
Environment
A. Alizadeh; H. Nowzari
Abstract
In the wildlife management, maintaining water quality and quantity, especially in areas that are faced with relative constraints of water resouces, are considered as one of the planning pillars. Natural springs and artificial troughs in the KooheHava and TangeKhoor Free Area are the only sources of water ...
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In the wildlife management, maintaining water quality and quantity, especially in areas that are faced with relative constraints of water resouces, are considered as one of the planning pillars. Natural springs and artificial troughs in the KooheHava and TangeKhoor Free Area are the only sources of water suppliers for wildlife of the area. The aim of this study was to investigate the microbial indices of water resources used by wildlife in this areas and to compare them with the Iranian national standard limit. In this study, 12 water sources including ten springs and two troughs were selected and sampling was carried out in two seasons of summer and autumn of 2020 and three samples from each water resources and a total of 72 samples were collected throughout the study period and the parameters of total coliform, fecal coliform, temperature, turbidity and pH were measured. The data were analyzed by One sample t-test, Paired sample t-test, Independent sample t-test, analysis of variance and Spearman correlation matrix. The results showed that the means of total coliform were higher than the standard limit in all samples with the exception of no. 4 and 12 springs and the means of fecal coliform were higher than the standard limit in all samples with the exception of no. 2, 4, 8, 10, 11 and 12 water resources both during summer and autumn. In summer, with increasing evaporation, the amount of pollution load of water resources was higher than autumn. However in autumn, the number of polluted water resources was higher which was due to the transmission of microbial contaminations caused by human and animal feces via rain. The results of correlation showed a decrease or an increase in turbidity, temperature or pH did not affect the amount of coliforms because despite the strong correlation between total coliform and fecal coliform, no correlation was found between them and physicochemical factors of water. Therefore, considering the temporal and spatial variability of fecal coliforms and their effect on disease, death and reduction of wildlife populations, optimizing and disinfection of water resources with chlorine and dredging them are recommended.
Environment
A. Ghalehnovi; H. Kamelnia
Abstract
Today, the focus on the sustainability issue in universities has become of significance considering the climatic and environmental issues. Therefore, universities are moving toward uniting the sustainability methods in their systems. Currently, many universities in Iran are performing essential activities ...
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Today, the focus on the sustainability issue in universities has become of significance considering the climatic and environmental issues. Therefore, universities are moving toward uniting the sustainability methods in their systems. Currently, many universities in Iran are performing essential activities in relation to environmental issues. This study is to determine the share of universities in sustainability quantitatively, and then it analyzes their activities. This research evaluates their activities in two steps based on the clustering and the efficiency of their performance. In the first step, the universities are grouped into homogenous clusters based on hierarchical clustering method with regards to their activities in sustainability area. Following that, the Comparative Table is used to calculate the gained percentage in each index based on the mean of the scores of each group using the data of the year 2021. This is done to have a better understanding of the performance of each cluster and the universities priorities for becoming greener and more successful in green-metric system. By evaluating the productivity and the efficiency of the universities, this study represents the most sustainable universities in group one (as the highly sustainable) and group two (as moderately sustainable) which have achieved the maximum grade in energy, transportation, research and instructive areas. These results also show that environmental variables (including water management, waste and infrastructure management) need to be taken into account by universities.
Environment
E. O. Dada; F. A. Oke; Y. O. Balogun
Abstract
Earthworms and crabs are known to influence the physicochemical state of their respective soil habitats through their bioturbation actions. While earthworm-bioturbated soils have been well documented to positively affect plant growth, not much is known about the effects of crab-bioturbated soil on plant ...
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Earthworms and crabs are known to influence the physicochemical state of their respective soil habitats through their bioturbation actions. While earthworm-bioturbated soils have been well documented to positively affect plant growth, not much is known about the effects of crab-bioturbated soil on plant growth. In this study, we compared the growth performance of four varieties of Phaseolus vulgaris (bean) seedlings in earthworm-bioturbated soil, crab-bioturbated soil, and unbioturbated soil collected within the same proximity of a wetland habitat. Seeds of Phaseolus vulgaris were planted in replicates in each soil type, and allowed to grow for 15 days. Physical growth was measured using a metre rule. Biochemical growth parameters were measured using standard procedures. The differences in stipule length of bean seedlings grown in all the soil types were generally not significant (p > 0.05). However, seedlings grown in earthworm-bioturbated soil and crab-boturbated soil recorded significantly higher (p < 0.05) stipule weight, relative to those grown in unbioturbated soil. Bean seedlings grown in earthworm-bioturbated soil recorded the highest and significant (p < 0.01) concentrations of chlorophyll, total sugar, starch, nitrogen, and crude protein, relative to those grown in crab-bioturbated and unbioturbated soils. This was followed by seedlings grown in crab-bioturbated soil which recorded significantly higher (p < 0.01) concentrations of these biochemical parameters, relative to those grown in unbioturbated soil. The significantly higher biochemical and marginally better physiological growth recorded for seedlings in bioturbated soils indicate that earthworms and crabs both contribute significantly to wetland productivity, through their bioturbatiion activities.
Environment
Z. Dorrani; H. Farsi; S. Mohamadzadeh
Abstract
In traffic monitoring for video analysis systems, vehicle shadows have a negative effect on their performance. Shadow detection and removal are essential steps in accurate vehicle detection. In this paper, a new method is proposed for shadow detection using a novel convolution neural network architecture. ...
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In traffic monitoring for video analysis systems, vehicle shadows have a negative effect on their performance. Shadow detection and removal are essential steps in accurate vehicle detection. In this paper, a new method is proposed for shadow detection using a novel convolution neural network architecture. In the proposed method, the edges of the image are first extracted. Edge extraction reduces calculation, and accelerates the execution of the method. The background of the frame is then removed and the main features are extracted using the ResUNet-a architecture. This architecture consists of two parts: the encoder and the decoder, which detect the shadow at the decoder output and then remove it. Deep learning is used to detect shadows, which increases the accuracy of the analysis. The ResUNet-a architecture can learn complex, hierarchical, and appropriate features from the image for accurate feature detection and discarding the irrelevant shadow, thereby outperforming conventional filters.The results show that the proposed method provides better performance on NJDOT traffic video, highway-1, and highway-3 datasets than popular shadow removal methods. Also, the method improves the evaluation criteria such as F-measure and runtime. The F-measure is 94 and 93% for highway-1 and highway-3, respectively.
Environment
A. A. Nurhanim
Abstract
Numbers of waste concrete have generated from construction and demolition waste (CDW) threaten environmental and human health due to the illegal dumping practices in several countries. Recently, the recycling of waste concrete has demonstrated the ability to reduce dependency on a natural resource in ...
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Numbers of waste concrete have generated from construction and demolition waste (CDW) threaten environmental and human health due to the illegal dumping practices in several countries. Recently, the recycling of waste concrete has demonstrated the ability to reduce dependency on a natural resource in producing building materials as well as reducing carbon footprint in the concrete manufacturing process. The objective is to determine the limitation factors of Waste Concrete Aggregate (WCA) as a replacement for virgin concrete aggregate. Analysis by X-Ray Diffraction (XRD), X-Ray Fluorescence (XRF), leaching, and sulphate tests were used to identify the physicochemical characteristics of WGA. Results showed WCA has high water absorption, expansion of Alkali-Silicate Reaction (ASR), low adhesive strength between aggregate and cement, leachability, and high soluble sulphate. CaO, Al2O3, SiO2, SO42-, Cr2O3, SrO, and Al2O3 were the main chemical components consisting of WCA. The leachability of Ca, Zn, and Cr in WCA was pH-dependent. High soluble sulphate content in WCA determined the extension formation of micro-crack in WCA due to extensively recrystallizing the Delay Ettringite Formation (DEF) in WCA. The formation of micro-crack, ASR, and low adhesive strength between aggregate and cement insides of WCA significantly affect the durability of recycled products in building structures. High water absorption and leachability of WCA enhanced the release of heavy metals in soil. Therefore, these limiting factors in WCA were necessarily treated before being utilized as a part of the recycled product.
Environment
S. O. Odeyemi; R. Abdulwahab; M. A. Akinpelu; R. Afolabi; O. D. Atoyebi
Abstract
The rising cost of concrete production due to the global recession in world economy caused by the COVID-19 pandemic and the greenhouse gases emitted in the production of cement has necessitated the need for alternative materials for cement. In this study, bamboo strips and steel rebars were used as reinforcements ...
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The rising cost of concrete production due to the global recession in world economy caused by the COVID-19 pandemic and the greenhouse gases emitted in the production of cement has necessitated the need for alternative materials for cement. In this study, bamboo strips and steel rebars were used as reinforcements in a ternary blended concrete to determine their strength properties. In alignment with standard requirements for testing, concrete specimens were tested at curing ages of 7, 14 and 28 days for compressive, splitting tensile and flexural strengths. The morphological and bond characteristics of the bamboo were determined through the Scanning Electron Microscopy (SEM) and Fourier Transform Infra-Red Spectroscopy (FTIR), respectively; while its tensile strength was determined and compared with that of steel reinforcement. These results showed that bamboo is ductile and has stretching vibrational spectrum. The combinations of quarry dust, river sand, Rice Husk Ash (RHA) and Guinea Corn Husk Ash (GCHA) yielded compressive and split tensile strengths of 20.4 N/mm2 and 2.18 N/mm2, respectively. Concrete with 50 % river sand and 50 % quarry dust performed better in flexure for both Bamboo Reinforced Concrete (BRC) and Steel Reinforced Concrete (SRC) at 28 days with strengths of 12.75 N/mm2 and 22.49 N/mm2, respectively. Therefore, bamboo, quarry dust, rice husk and guinea corn husk ash can be used for reinforced concrete production.
Environment
S. V. Mojtahed Sistani; H. Negahdar; F. F. Bamoharram; M. R. Shakeri
Abstract
Soil polluted with urban wastewater due to defect of wastewater disposal and leakage from wastewater channels is a common type of pollution in urban areas which in addition to environmental damage, has significant effects on soil engineering parameters. In present study, effects of municipal wastewater ...
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Soil polluted with urban wastewater due to defect of wastewater disposal and leakage from wastewater channels is a common type of pollution in urban areas which in addition to environmental damage, has significant effects on soil engineering parameters. In present study, effects of municipal wastewater on mechanical behavior of soil and clay microstructure was studied, and then effects of iron oxide nanoparticles on remediation trend of contaminated soil was investigated. To achieve this, unconfined compressive strength (UCS), collapse and SEM analysis tests were performed on contaminated samples containing 20%, 60% and 100% wastewater at 1, 3 and 5 months and also on contaminated soil remidiated with 0.5-4% Iron nano oxide. Results showed that wastewater reduces shear strength of clay and this decreasing trend increases with increasing percentage and contamination duration. UCS of soil contaminated with 100% wastewater decreased by 49% after 5 months of contamination. Also, wastewater in the soil caused to soil collapse after 5 months . SEM images showed the clay structure became clotted after contamination and soil pores increased compared to natural soil. Improvement phase results showed that by addition of Iron nano oxide to contaminated soil, shear strength significantly increased, and optimal percentage of Iron nano oxide was 3% in which UCS increased by 105.2%. By increasing the percentage of Iron nanoxide, intensity of collapse index of contaminated soil decreases. Best case senario, final strain of soil decreases by 43.4% compared to contaminated soil. Therefore, utilizing Iron nanooxide is recommended to improve engineering behavior of contaminated clay.
Environment
O. F. Anjorin; L. C. Imoh; C. Uhunmwangho
Abstract
Biomass use in small unit combustion systems such as for space heating or cooking could lead to ineffective mixing and potential problems arising from emissions of gaseous and particulate pollutants. We therefore conducted a study to measure pollution levels in public kitchens using biomass fuel for ...
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Biomass use in small unit combustion systems such as for space heating or cooking could lead to ineffective mixing and potential problems arising from emissions of gaseous and particulate pollutants. We therefore conducted a study to measure pollution levels in public kitchens using biomass fuel for cooking and to ascertain their air quality indices. Markers of indoor air quality such as CO, SO2, H2S, PM2.5 and PM10 were measured in eleven (11) public kitchens of selected secondary schools over a period of four months by a set of active sampling devices. It is revealed that the mean average of CO, SO2, H2S, PM2.5 and PM10 sampled in the indoor microenvironments of the selected kitchens are 46.29 ppm, 0.36 ppm, 0.28 ppm, 74 µg/m3 and 138 µg/m3, respectively. The AQI assessed for CO for the kitchens was 36.36% very hazardous, 54.54 % hazardous and 9.09% very unhealthy while 63.64% and 36.36 % of very unhealthy and unhealthy categories, respectively for SO2. This shows that the indoor air pollution levels in selected kitchen are elevated and results in potential negative health consequences.
